| 摘要 |
PURPOSE:To correct two-bit error by means of a simple circuit change in ECC of one-bit error correction and two-bit (or above) error detection. CONSTITUTION:This circuit is provided with an ECC circuit 1 having the generation function of a check bit in write data, a one-bit error correction function in read data, a two-bit error detection function and three or more bits error detection function, ac ECC control circuit 3 controlling the ECC circuit 1 and bit inversion circuit 2 having a function which bit-inverts only specified read data by the instruction of the ECC control circuit 3. When the two-bit error is detected in the read data at the ECC circuit 2, the bit inversion circuit 1 inverts all read data including a checking code one by one bit and the ECC circuit 1 corrects the two-bit error at the time of the one-bit error. |
